KR20120138688A - Liquid crystal lens and display including the same - Google Patents

Abstract

PURPOSE: A liquid crystal lens and a display device including the same are provided to conveniently find a viewpoint for three-dimensional images by easily adjusting focus distance. CONSTITUTION: A liquid crystal lens(1100) includes a first electrode(110), a second electrode(120), a liquid crystal layer(130), and a dielectric layer(140). The first and the second electrodes face each other. The liquid crystal layer lies between the first and the second electrodes, and has flat upper and lower surfaces. The dielectric layer lies between the second electrode and the liquid crystal layer. The dielectric layer includes the capacitance varying range in the horizontal direction between the upper and the lower surfaces.

Description

Liquid crystal lens and display including the same {Liquid crystal lens and display including the same}

The present invention relates to a liquid crystal lens and a display device including the same, and more particularly, to a liquid crystal lens for controlling an optical path and a display device including the same.

The display device emits light in various ways to display an image. The manner in which the display device emits light also serves as a criterion for distinguishing types of display devices. Various studies have been made to competitively control the luminance of light emitted for each light emission method and to improve display quality.

In recent years, research on a stereoscopic image display device that realizes a 3D image through optical path control has been in the spotlight apart from the optical luminance control. The basic principle is that if a left eye image is provided to the observer's left eye and a right eye image is provided to the observer's right eye, the observer can recognize it in three dimensions. Polarization, time-division, or parallax-barrier, lenticular or micro-lens, and blinking lights, which correspond to eyeglasses, are mainly studied.

 On the other hand, if you watch only three-dimensional image for a long time can feel dizziness. In addition, the viewer may want to watch not only the 3D video content but also the 2D video content.

If the light path can be controlled differently for each mode, it is possible to display both 2D and 3D images. Freely controlling the optical path can create not only a display device but also various application fields using light.

The problem to be solved by the present invention is to provide a liquid crystal lens capable of adjusting the optical path.

Another object of the present invention is to provide a display device capable of adjusting an optical path.

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

The liquid crystal lens according to an embodiment of the present invention for solving the above problems is interposed between the first electrode and the second electrode, the first electrode and the second electrode facing each other, the upper and lower surfaces of the liquid crystal layer, And a dielectric layer interposed between the second electrode and the liquid crystal layer, wherein the dielectric layer includes a section in which capacitance between upper and lower surfaces of the dielectric layer varies along a horizontal direction.

Liquid crystal lens according to another embodiment of the present invention for solving the above problems is interposed between the first electrode and the second electrode, the first electrode and the second electrode facing each other, the upper and lower surfaces of the liquid crystal layer, And a dielectric layer interposed between the second electrode and the liquid crystal layer, the dielectric layer including a first sub dielectric layer having a first dielectric constant and a second sub dielectric layer having a second dielectric constant different from the first dielectric constant. The dielectric layer may include a section in which a height of at least one of the first sub dielectric layer and the second sub dielectric layer is changed along the horizontal direction.

The liquid crystal lens according to another embodiment of the present invention for solving the above problems is formed on the first electrode, the liquid crystal layer having a flat upper and lower surfaces on the first electrode, the liquid crystal layer, the upper surface includes a curved surface And a second electrode conformally formed on the top surface of the dielectric layer.

According to another aspect of the present invention, there is provided a display device and a liquid crystal lens disposed on the light providing device, the first and second electrodes opposing each other, and the first electrode. And a liquid crystal layer interposed between the second electrodes and having flat top and bottom surfaces, and a dielectric layer interposed between the second electrode and the liquid crystal layer, wherein the dielectric layer has a horizontal capacitance between the top and bottom surfaces of the dielectric layer. It includes a liquid crystal lens including a section that changes along the direction.

According to another aspect of the present invention, a display device and a liquid crystal lens disposed on the light providing device may include a first electrode and a second electrode facing each other, and the first electrode. And a liquid crystal layer interposed between the second electrodes, the upper and lower surfaces of which are flat, and a dielectric layer interposed between the second electrode and the liquid crystal layer, the first sub dielectric layer having a first dielectric constant, and the first dielectric constant. A liquid crystal lens comprising a dielectric layer including a second sub dielectric layer having a different second dielectric constant, wherein the dielectric layer includes a section in which a height of at least one of the first sub dielectric layer and the second sub dielectric layer varies along the horizontal direction. It includes.

According to another aspect of the present invention, a display device and a liquid crystal lens disposed on the light providing device may include a first electrode and a top and bottom surfaces thereof. And a liquid crystal lens including a flat liquid crystal layer, a dielectric layer formed on the liquid crystal layer and having an upper surface curved thereon, and a second electrode conformally formed on the upper surface of the dielectric layer.

The details of other embodiments are included in the detailed description and drawings.

According to embodiments of the present invention has at least the following effects.

That is, according to the liquid crystal lens according to the embodiments of the present invention, various optical paths may be adjusted. Therefore, the present invention can be applied to various devices using light such as a display device, a solar cell, an image sensor, and the like. In addition, in the case of the display device employing the liquid crystal lens according to the embodiments of the present invention, since various optical paths can be adjusted, 2D / 3D switching is possible, so that both 3D and 2D images can be displayed. have. Furthermore, since the focal length can be easily adjusted, the viewpoint of viewing the 3D image can be conveniently found.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a schematic configuration diagram of a display device according to an exemplary embodiment of the present invention.
2 is a cross-sectional view of a liquid crystal lens according to an exemplary embodiment of the present invention.
FIG. 3A is a graph illustrating the permittivity of each dielectric layer of FIG.
FIG. 3B is a graph showing the location-specific elastomers of the dielectric layer of FIG. 2.
4 is a schematic diagram illustrating an operation of a first mode of a liquid crystal lens according to an exemplary embodiment of the present invention.
FIG. 5 is a graph illustrating refractive indices for respective horizontal positions of the liquid crystal layer in the first mode of the liquid crystal lens according to the exemplary embodiment. FIG.
6 is a schematic diagram illustrating an operation of a second mode of a liquid crystal lens according to an exemplary embodiment of the present invention.
FIG. 7 is a graph showing refractive indices for respective horizontal positions of the liquid crystal layer in the second mode of the liquid crystal lens according to the exemplary embodiment.
8 is a cross-sectional view of a liquid crystal lens according to another exemplary embodiment of the present invention.
FIG. 9 is a graph illustrating permittivity of each dielectric layer of FIG. 8 according to positions.
10 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention.
FIG. 11 is a graph illustrating permittivity of each dielectric layer of FIG. 10 according to positions.
12 is a cross-sectional view of a liquid crystal lens according to another embodiment of the present invention.
FIG. 13 is a graph illustrating permittivity of each dielectric layer of FIG. 12 according to positions.
14 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention.
FIG. 15 is a graph illustrating a distribution of elastance according to positions of the dielectric layer of FIG. 14.
16 to 21 are cross-sectional views of liquid crystal lenses according to various embodiments of the present disclosure.
FIG. 22 is a cross-sectional view illustrating an exemplary method of manufacturing the dielectric layer of FIG. 21.
FIG. 23 is a cross-sectional view illustrating another exemplary method of manufacturing the dielectric layer of FIG. 21.
24 to 34 are cross-sectional views of liquid crystal lenses according to various embodiments of the present disclosure.
35 is a cross-sectional view of a display device according to an exemplary embodiment of the present invention.
36 is a cross-sectional view for describing an exemplary operation of the display device in the second mode.

Advantages and features of the present invention, and methods of achieving the same will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

References to elements or layers "on" other elements or layers include all instances where another layer or other element is directly over or in the middle of another element. Like reference numerals refer to like elements throughout.

Although the first, second, etc. are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may be the second component within the technical scope of the present invention.

In the present specification, the term "elastance" means the inverse of capacitance (1 / C).

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention.

1 is a schematic configuration diagram of a display device according to an exemplary embodiment of the present invention. Referring to FIG. 1, the display device 30 includes a light providing device 20 and a liquid crystal lens 10 disposed on one side of the light providing device 20.

The light providing device 20 provides light to the liquid crystal lens 10. The light provided by the light providing device 20 to the liquid crystal lens 10 is emitted from the light providing device 20 and / or reflected light that is incident from the liquid crystal lens 10 and reflected by the light providing device 20. It may include.

The light providing device 20 may include a display panel. In some embodiments, the display panel may be an organic light emitting diode (OLED), an LED, an electroluminescent display (EL), a field emission display (FED), a surface-conduction electron-emitter display (SED), a plasma display panel (PDP). And a self-luminous display panel such as a cathode ray tube (CRT). In some other embodiments, the display panel may be a non-light emitting display panel such as a liquid crystal display (LCD), an electrophoretic display (EPD), or the like. When the display panel is a non-light emitting display panel, the light providing device 20 may further include a light source such as a backlight assembly.

The liquid crystal lens 10 is disposed on one side of the light providing device 20 to receive the light emitted from the light providing device 10. The liquid crystal lens 10 at least partially modulates optical characteristics such as a path and a phase of incident light. In some embodiments, the optical characteristic modulation of the liquid crystal lens 10 may differ depending on the mode. For example, the liquid crystal lens 10 does not modulate the optical characteristic in the first mode, but the liquid crystal lens 10 may modulate the optical characteristic in the second mode. By modulating the light modulation characteristics differently for each mode, the image emitted from the display panel of the light providing apparatus 20 may be modulated differently for each mode, and accordingly, the image emitted through the liquid crystal lens 10 may be controlled differently for each mode. have. Such selective optical modulation characteristics of the liquid crystal lens 10 for each mode enable the display capable of 2D / 3D switching as described below.

Hereinafter, a liquid crystal lens according to an embodiment of the present invention will be described in more detail. 2 is a cross-sectional view of a liquid crystal lens according to an exemplary embodiment of the present invention. Referring to FIG. 2, the liquid crystal lens 1100 includes a liquid crystal layer 130 interposed between the first electrode 110 and the second electrode 120, and the first electrode 110 and the second electrode 120 facing each other. ) And the dielectric layer 140.

Each of the first electrode 110 and the second electrode 120 may be made of a transparent conductive material. For example, it may be formed of an oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZO), indium oxide (IO), titanium oxide (TiO), or the like. As another example, the material may include a material such as carbon nanotube (CNT), metal nanowire, or conductive polymer. The first electrode 110 and the second electrode 120 are not necessarily made of the same material.

The first electrode 110 receives a first voltage and the second electrode 120 receives a second voltage. Therefore, a predetermined electric field corresponding to the difference between the first voltage and the second voltage may be formed between the upper surface 110a of the first electrode 110 and the lower surface 120b of the second electrode 120.

In some embodiments of the present invention, the first electrode 110 and the second electrode 120 may each be a whole surface electrode that is not patterned. The first electrode 110 and the second electrode 120 may be arranged in parallel to each other.

The liquid crystal layer 130 and the dielectric layer 140 are interposed between the first electrode 110 and the second electrode 120. In FIG. 2, an example in which the liquid crystal layer 130 is stacked on the first electrode 110 and the dielectric layer 140 is stacked on the liquid crystal layer 130 is illustrated. The stacking order can be reversed.

The upper surface 130_1 and the lower surface 130_2 of the liquid crystal layer 130 may be substantially flat. If the upper surface 130_1 and the lower surface 130_2 of the liquid crystal layer 130 are flat, it may be advantageous to uniformly distribute the liquid crystal molecules 135. Furthermore, the upper surface 130_1 and the lower surface 130_2 of the liquid crystal layer 130 may be parallel to each other.

The liquid crystal layer 130 includes a plurality of liquid crystal molecules 135 in the space defined by the upper surface 130_1 and the lower surface 130_2. The liquid crystal molecules 135 may be uniformly distributed over the entire area of the liquid crystal layer 130. In the present embodiment, the liquid crystal molecules 135 have positive dielectric anisotropy and are initially oriented in the horizontal direction. Here, the alignment in the horizontal direction may be a state in which the long axis of the liquid crystal molecules 135 is disposed parallel to the horizontal direction, for example, a state in which the azimuth angle of the liquid crystal molecules 135 is 0 °.

In some other embodiments of the present invention, the liquid crystal molecules 135 may have negative dielectric anisotropy. In this case, the liquid crystal molecules 135 may be initially aligned in the vertical direction. Here, the initial orientation in the vertical direction includes not only a case where the azimuth angle of the liquid crystal molecules 135 is 90 ° but also a case in which the liquid crystal molecules 135 are pretilted by a predetermined angle. In this regard, the azimuth angle of the liquid crystal molecules 135 initially oriented in the vertical direction may be, for example, 80 ° to 90 °.

The dielectric layer 140 includes at least one dielectric material. When the horizontal direction of the liquid crystal lens 1100 is referred to as the first direction X, and the thickness direction perpendicular thereto, that is, the direction in which the liquid crystal layer 130 and the dielectric layer 140 are stacked is referred to as the second direction Y, The capacitance C between the top surface 140_1 and the bottom surface 140_2 of the dielectric layer 140 may be at least partially different from each other along the first direction X. FIG. That is, the dielectric layer 140 includes a section in which the capacitance C between the upper surface 140_1 and the lower surface 140_2 of the dielectric layer 140 changes along the first direction X. FIG. When the distance between the top surface 140_1 and the bottom surface 140_2 of the dielectric layer 140 remains the same along the first direction X, for example, the top surface 140_1 and the bottom surface 140_2 of the dielectric layer 140 are respectively flat. And, when parallel to each other, the capacitance (C) different from location to location may be implemented by different permittivity by location.

The liquid crystal lens 110 may include two or more unit lens sections L1 and L2 according to the distribution of the capacitance C of the dielectric layer 140 or the distribution of the dielectric constant. Each unit lens section L1 and L2 may exhibit optical characteristics similar to those of an optical lens such as a convex lens and a concave lens, depending on the voltage applied to the first electrode 110 and the second electrode 120. Optical characteristics of each unit lens section L1 and L2 may vary according to voltages applied to the first electrode 110 and the second electrode 120. That is, each unit lens section L1 and L2 may function as a variable lens.

It can be understood that a single optical lens exhibits a single light modulation characteristic. For example, in the case of a convex lens, although the degree of refraction and the like is different depending on the position where light is incident on the lens surface, it is understood that they are collectively exhibiting one integrated light modulation characteristic of condensing, for example. In this regard, each unit lens section L1 and L2 of the liquid crystal lens 1100 may have a separate light modulation characteristic corresponding to the optical lens. That is, the first unit lens section L1 may represent the first light modulation characteristic, and the second unit lens section L2 may represent the second light modulation characteristic. The first light modulation characteristic and the second light modulation characteristic may be substantially the same. For example, the first light modulation characteristic and the second light modulation characteristic may both represent the optical characteristics of the same convex lens. In this case, the first unit lens section L1 and the second unit lens section L2 may operate as if two identical convex lenses are optically arranged.

In order to describe the light modulation characteristics of each unit lens section L1 and L2 in detail, not only FIG. 2 but also FIGS. 3A to 7 are referred to together.

FIG. 3A is a graph illustrating the permittivity of each dielectric layer of FIG. FIG. 3B is a graph showing the location-specific elastomers of the dielectric layer of FIG. 2. 2 and 3A, in the first unit lens section L1, the dielectric constant of the dielectric layer 140 decreases toward the P1 direction from the point P0 and then increases again to draw a convex parabola graph. In the second unit lens section L2, the dielectric constant of the dielectric layer decreases in the direction from the point P1 to the direction P2 and then increases again to form a convex parabola graph. The parabolic graphs of the first unit lens section L1 and the second unit lens section L2 may be identical to each other. That is, the distribution of permittivity according to the same position in the horizontal direction for each unit lens section L1 and L2 may be the same. In this case, the first unit lens section L1 and the second unit lens section L2 of the present exemplary embodiment may exhibit substantially the same electrical and optical characteristics.

If the distance between the top surface 140_1 and the bottom surface 140_2 of the dielectric layer 140 is constant along the first direction X, the capacitance of the dielectric layer 140 is proportional to the dielectric constant, so that the graph of the capacitance is substantially different from that of FIG. 3A. The same pattern can be represented by. Thus, the graph of the distribution of the elastance (1 / C), which is the inverse of the dielectric layer 140 capacitance, may be substantially the same as upside down the graph of the dielectric constant distribution of the dielectric layer 140, as shown in FIG. 3B. have. Therefore, the elastance 1 / C can be maximized at the horizontal point where the dielectric constant is minimum.

In addition, if the permittivity according to the same position in the horizontal direction in each unit lens section (L1, L2) is the same, the distribution of capacitance or elastance according to the same position in the horizontal direction may also be the same.

The operation of the liquid crystal lens 1100 having the above configuration will be described. 4 is a schematic diagram illustrating an operation of a first mode of a liquid crystal lens according to an exemplary embodiment of the present invention. FIG. 5 is a graph illustrating refractive indices for respective horizontal positions of the liquid crystal layer in the first mode of the liquid crystal lens according to the exemplary embodiment. FIG.

4 and 5, in the first mode of the liquid crystal lens 1100, the liquid crystal molecules 135 of the liquid crystal layer 130 are arranged at the same azimuth angle regardless of the position of the first direction X in the horizontal direction. Mode. For example, the first mode may be implemented by applying the same voltage to the first electrode 110 and the second electrode 120. When the same voltage is applied to the first electrode 110 and the second electrode 120, the potential difference V1 applied to the dielectric layer 140 and the liquid crystal layer 130 is 0V. Since no voltage is applied to the liquid crystal layer 130, the liquid crystal molecules 135 maintain a horizontal direction, which is an initial alignment direction. Accordingly, the light incident on the liquid crystal lens 1100 may feel the same refractive index regardless of the horizontal position of the liquid crystal layer 130 as shown in FIG. 5. Therefore, the light incident on the liquid crystal layer 130 goes straight in the liquid crystal layer 130 without changing the light propagation path.

When the light passing through the liquid crystal layer 130 reaches the dielectric layer 140, if the refractive index of the dielectric layer 140 is the same as the refractive index of the liquid crystal layer 130, the light does not recognize the dielectric layer 140 as an optically different material. Do not. Therefore, the light is transmitted as it is without changing the light path. If the refractive index of the liquid crystal layer 130 and the dielectric layer 140 are different from each other, most of the light passing through the liquid crystal layer 140 vertically causes only a change in wavelength at an interface having different refractive indices, but the optical path is not changed. Do not.

Furthermore, even if the dielectric layer 140 is made of two or more different materials, if they have the same refractive index, the optical path at the interface is not changed. If made of a material having a refractive index of 2 or more, the light path does not change if light is incident perpendicularly to the interface. Therefore, as shown in FIG. 4, light incident on the liquid crystal lens 1100 passes through the liquid crystal layer 130 and the dielectric layer 140 as it is.

6 is a schematic diagram illustrating an operation of a second mode of a liquid crystal lens according to an exemplary embodiment of the present invention. FIG. 7 is a graph showing refractive indices for respective horizontal positions of the liquid crystal layer in the second mode of the liquid crystal lens according to the exemplary embodiment.

6 and 7, the second mode of the liquid crystal lens 1100 is a mode in which the liquid crystal molecules 135 of the liquid crystal layer 130 are arranged to have at least partially different azimuth angles according to horizontal positions. For example, when different voltages are applied to the first electrode 110 and the second electrode 120, and a predetermined electric field is formed therebetween, the second mode may be driven. In the second mode, an electric field for each position is the same between the upper surface 110a of the first electrode 110 and the lower surface 120a of the second electrode 120 along the horizontal direction. However, in view of the liquid crystal layer 130, the electric fields of the upper and lower surfaces 130_1 and 130_2 are different for each position in the horizontal direction.

More specifically, the liquid crystal layer 130 and the dielectric layer 140 are interposed between the first electrode 110 and the second electrode 120. Since the lower surface 130_2 of the liquid crystal layer 130 is adjacent to the first electrode 110, the first voltage may be applied as it is regardless of the horizontal position. However, the upper surface 130_1 of the liquid crystal layer 130 is interposed between the first electrode 110 and the liquid crystal layer 130, and the dielectric layer 140 is interposed between the second electrode 120 and the second electrode 120. The liquid crystal layer 130 constitutes a first capacitor having a first capacitance between the upper surface 130_1 and the lower surface 130_2, and the dielectric layer 140 has a second capacitance between the upper surface 140_1 and the lower surface 140_2. A second capacitor is configured. In the equivalent circuit, the first capacitor and the second capacitor are connected in series. On the other hand, the voltage across a plurality of capacitors connected in series is inversely proportional to the magnitude (C) of the capacitance of each capacitor, and is proportional to the elastance (1 / C).

The upper surface 130_1 of the liquid crystal layer 130, that is, the lower surface 140_2 of the dielectric layer corresponds to a value between the first voltage applied to the first electrode 110 and the second voltage applied to the second electrode 120. If a voltage is applied, and the capacitance of the dielectric layer 140 is large, the magnitude of the voltage applied to the upper and lower surfaces of the dielectric layer 140 is relatively small. Therefore, the voltage applied to the upper surface 130_1 of the liquid crystal layer 130 is relatively different from the first voltage. Similarly, if the capacitance of the dielectric layer 140 is small, the voltage applied to the upper surface 130_1 of the liquid crystal layer 130 is relatively small from the first voltage.

However, as described with reference to FIGS. 3A and 3B, since the dielectric layers 140 have different dielectric constants and capacitances in the horizontal direction, voltages applied to the upper surface 130_1 of the liquid crystal layer 130 also differ. In a period in which the dielectric constant of the dielectric layer 140 is large (a period in which the capacitance is large), a voltage having a large difference from the first voltage is applied to the upper surface 130_1 of the liquid crystal layer 130. As a result, the magnitude of the electric field applied to the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 increases. Since a voltage having a small difference from the first voltage is applied to the upper surface 130_1 of the liquid crystal layer 130 in a region having a low dielectric constant of the dielectric layer 140 (a region having a small capacitance), the upper and lower surfaces of the liquid crystal layer 130 ( 130_1 and 130_2 become smaller in size.

As described above, since the liquid crystal molecules 135 have positive dielectric anisotropy in the present embodiment, the larger the electric field, the more the electric field rotates. Therefore, as shown in FIG. 6, the arrangement of the liquid crystal molecules 135 is a region in which the liquid crystal molecules 135 rotate in the vertical direction and the dielectric constant of the dielectric layer 140 is large in a region where the dielectric constant of the dielectric layer 140 is small. In this case, the liquid crystal molecules 135 rotate relatively less.

On the other hand, the liquid crystal molecules 135 also have anisotropy with respect to the refractive index. That is, the liquid crystal molecules 135 optically exhibit two types of refractive indices: normal ray refractive index no for light in the long axis direction and extraordinary ray refractive index ne for light in the axial direction. Have Here, the normal ray refractive index no may be smaller than the abnormal ray refractive index ne. For example, the normal ray refractive index no of the liquid crystal molecules 135 may be about 1.5, and the abnormal ray refractive index ne of the liquid crystal molecules 135 may be about 1.7.

Therefore, when the liquid crystal molecules 135 are arranged horizontally, the light is exposed to the extraneous ray refractive index ne, so that the refractive index becomes relatively large. On the other hand, when the liquid crystal molecules 135 rotate in the vertical direction, the light may feel relatively smaller normal ray refractive index no, and thus the refractive index becomes smaller. Therefore, the refractive index according to the position of the first direction X of the liquid crystal layer 130 may have a distribution as shown in FIG. 7. Comparing FIG. 7 with FIG. 3B, the graph of the distribution of refractive indices is substantially the same as the graph of the distribution of elastance, which is the inverse of the capacitance. Therefore, the refractive index is maximized at the horizontal point where the capacitance is minimum.

In the medium having a uniform refractive index, the light travels in a straight line. However, in the green (GRIN, Gradient Index) lens structure in which the refractive index gradually changes in the medium, as shown in FIG. 7, the optical path is bent toward the medium having the high refractive index. All. The structure and operation principle of the green lens are disclosed in US Pat. No. 5,790,314, the contents of which are incorporated and incorporated as if fully disclosed herein.

Therefore, in the second mode, the light passing through the liquid crystal layer 130 may be bent toward the medium having a high refractive index, and thus may exhibit a light traveling path as shown in FIG. 6. The modulation of the light propagation path of FIG. 6 is similar to the light propagation path through the convex lens. That is, in the second mode, the liquid crystal layer 130 of the liquid crystal lens 1100 may collect light without a separate convex lens.

The light passing through the liquid crystal layer 130 reaches the interface of the dielectric layer 140, and the curved light passing through the liquid crystal layer 130 is incident on the dielectric layer 140 at a predetermined incident angle. When the dielectric layer 140 has substantially the same refractive index as that of the liquid crystal layer 130, the dielectric layer 140 proceeds without changing the optical path. When the dielectric layer 140 has a refractive index different from that of the liquid crystal layer 130, light is refracted at the interface. If the refractive index of the dielectric layer 140 is smaller than that of the liquid crystal layer 130, the focal length that is concentrated by refracting at an angle larger than the incident angle according to Snell's law will be reduced. On the contrary, if the refractive index of the dielectric layer 140 is larger than that of the liquid crystal layer 130, the reverse will be apparent.

The magnitudes of the first voltage and the second voltage not only determine the first mode and the second mode, but also control the light modulation characteristics differently within the same second mode. As described above, when the same voltage is applied to the first electrode 110 and the second electrode 120, the liquid crystal lens 1100 is driven as the first mode. On the other hand, even when the difference between the first voltage and the second voltage is very large, it can be driven in the first mode. For example, assuming that an extreme difference between the first voltage and the second voltage is infinite, the upper surface of the liquid crystal layer 130 may be different even if the voltage applied to the upper surface 130_1 of the liquid crystal layer 130 is different depending on the horizontal position. Since the absolute value of the voltage difference between the voltage at 130_1 and the lower surface 130_2 of the liquid crystal layer 130 is very large, all of the liquid crystal molecules 135 may rotate in the vertical direction. That is, since the azimuth angles of all the liquid crystal molecules 135 of the liquid crystal layer 130 are the same as 90 °, the light passing through the liquid crystal layer 130 will feel the refractive index of the normal light regardless of the position in the horizontal direction. . In this case, since the green lens is not configured, the light is straight without being bent in the liquid crystal layer 130.

Meanwhile, although the first voltage and the second voltage have different values, the difference is so small that the maximum value of the electric field applied to the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 is for rotating the liquid crystal molecules 135. If the threshold electric field level is not exceeded, even in this case, all liquid crystal molecules 135 may maintain a horizontal alignment. Therefore, since the green lens is not configured, the light is straight without being bent in the liquid crystal layer 130.

From the above, it can be seen that the condition for driving the second mode of the liquid crystal lens 130 is not simply satisfied that the first voltage and the second voltage are different, and the difference between the first voltage and the second voltage should be within a predetermined range. have. That is, due to the difference between the first voltage and the second voltage, the maximum value of the electric field applied to the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 should be greater than the threshold electric field level for rotating the liquid crystal molecules 135. Due to the difference between the first voltage and the second voltage, the minimum value of the electric field applied to the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 is higher than the electric field capable of rotating the liquid crystal molecules 135 vertically (azimuth angle of 90 °). Should be small.

On the other hand, even if the liquid crystal lens 1100 is driven in the second mode, the distribution of the refractive index may be different according to the difference between the first voltage and the second voltage. That is, the difference between the first voltage and the second voltage variously controls the curvature of the green lens illustrated in FIG. 7. It is apparent that different focal lengths can be adjusted accordingly.

Detailed conditions for driving the first mode and the second mode as described above, the method of controlling the focal length of the second mode, etc. are described by those skilled in the art based on the dielectric constant of the dielectric, the type of liquid crystal molecules, etc. Since it may be easily implemented by appropriately adjusting the first voltage and the second voltage, specific examples will be omitted in order to avoid obscuring the present invention.

In the above embodiment, the liquid crystal lens 1100 has two unit lens sections L1 and L2. However, the liquid crystal lens 1100 may include three or more unit lens sections, which is the same in the following embodiments. .

Hereinafter, a liquid crystal lens according to various embodiments of the present disclosure will be described.

In some embodiments of the present invention, the liquid crystal lenses may have different light modulation characteristics in the first unit lens section and the second unit lens section. 8 to 11 illustrate liquid crystal lenses having such characteristics.

8 is a cross-sectional view of a liquid crystal lens according to another exemplary embodiment of the present invention. FIG. 9 is a graph illustrating permittivity of each dielectric layer of FIG. 8 according to positions. 8 and 9, the liquid crystal lens 1101 according to the present exemplary embodiment may have a horizontal position having a minimum dielectric constant of the dielectric layer 140a of the first unit lens section L1 and a dielectric layer of the second unit lens section L2. (140a) The horizontal positions having the dielectric constant minimum are different from each other. That is, the minimum value of the dielectric constant in the first unit lens section L1 is present at the right side with respect to the intermediate point between the P0 point and the P1 point. On the other hand, the minimum value of the dielectric constant in the second unit lens section L2 is present on the left side based on the intermediate point between the P1 point and the P2 point. Accordingly, as shown in FIG. 8, the light traveling path in the first unit lens section L1 is biased to the right as compared with FIG. 6, while the light traveling path in the second unit lens section L2 is It is relatively biased to the left.

10 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. FIG. 11 is a graph illustrating permittivity of each dielectric layer of FIG. 10 according to positions. 10 and 11, the liquid crystal lens 1102 according to the present exemplary embodiment may have a maximum value of the dielectric constant of the first unit lens section L1 dielectric layer 140b and a dielectric constant of the second unit lens section L2 dielectric layer 140b. The maximum values of are different from each other. Accordingly, as shown in FIG. 11, the dielectric constant graph curvature of the first unit lens region L1 dielectric layer 140b is greater than the dielectric constant graph curvature of the second unit lens interval dielectric layer 140b.

Accordingly, the amount of change in permittivity of the first unit lens section L1 is large, and thus, the horizontal change rate of the electric field applied to the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 is also larger than the first unit lens section L1. As a result, as shown in FIG. 10, the difference in the azimuth angles of the liquid crystal molecules 135 in the first unit lens section L1 for each horizontal position is greater when the second mode is driven, and the change rate of the refractive index of the liquid crystal molecules 135 is also increased. The light propagation path may be bent more than the second unit lens section L2. Therefore, the optical focal length in the first unit lens section L1 may be shorter than the optical focal length in the second unit lens section L2.

Although not shown in the drawings, in the case of the liquid crystal lens according to some other embodiments of the present invention, the dielectric layer of the first unit lens section has a different dielectric constant depending on the horizontal position as illustrated in FIG. The dielectric layer may have the same dielectric constant regardless of the horizontal position. In this case, the first unit lens section of the liquid crystal lens has a light modulation characteristic similar to that of the convex lens in the second mode, but in the case of the second unit lens section, only the first mode in which the light modulation is not performed internally is driven. .

12 is a cross-sectional view of a liquid crystal lens according to another embodiment of the present invention. FIG. 13 is a graph illustrating permittivity of each dielectric layer of FIG. 12 according to positions. 12 and 13, in the liquid crystal lens 1103 according to the present exemplary embodiment, the dielectric constant of the dielectric layer 140c increases in the first unit lens section L1 from the point P0 toward the P1 direction and then decreases again. Draw a convex parabolic graph. In the case of the second unit lens section L2, a substantially same graph is formed. Thus, the distribution of refractive indices will form a convex downwards. As described above, in the green lens structure, since the optical path is bent from the medium having a low refractive index to the medium having a high refractive index, the liquid crystal layer 130 of FIG. 12 causes modulation of the light propagation path similar to that of the concave lens in the second mode. . That is, in the second mode, the liquid crystal layer 130 of the liquid crystal lens may emit or diffuse light without a separate concave lens.

The embodiments described above may be combined in various ways.

Subsequently, specific embodiments of controlling the dielectric constant of the dielectric layer along the horizontal direction will be described. The same components or members as in the previous embodiment will be given the same reference numerals, and description thereof will be omitted or simplified.

14 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. FIG. 15 is a graph showing values of the elastance (1 / C) for each position of the dielectric layer of FIG. 14.

Referring to FIG. 14, the liquid crystal lens according to the present exemplary embodiment includes a liquid crystal layer interposed between the first electrode 110 and the second electrode 120, and the first electrode 110 and the second electrode 120 facing each other. 130 and dielectric layer 141. The dielectric layer 141 includes a first sub dielectric layer 141a and a second sub dielectric layer 141b.

The first electrode 110 may be formed on the first substrate 101. The second electrode 120 may be formed on the second substrate 102. The first substrate 101 and the second substrate 102 may be transparent substrates. For example, the first substrate 101 and the second substrate 102 may be formed of a transparent plastic substrate, a transparent glass substrate, a transparent quartz substrate, or the like. In some embodiments, at least one of the first substrate 101 and the second substrate 102 may be a flexible substrate.

The liquid crystal layer 130 is formed on the first electrode 110. The upper surface 130_1 and the lower surface 130_2 of the liquid crystal layer 130 may be substantially flat. Furthermore, the upper surface 130_1 and the lower surface 130_2 of the liquid crystal layer 130 may be parallel to each other. Although not illustrated, a first alignment layer may be interposed between the first electrode 110 and the bottom surface 130_1 of the liquid crystal layer 130 to initially align the liquid crystal molecules 135 in the liquid crystal layer 130.

The dielectric layer 141 is formed on the liquid crystal layer 130. A second alignment layer (not shown) may be interposed between the upper surface 130_1 of the liquid crystal layer 130 and the lower surface 141_2 of the dielectric layer 141. The top surface 141_1 and the bottom surface 141_2 of the dielectric layer 141 may each be flat and may further be parallel to each other.

The dielectric layer 141 includes a first sub dielectric layer 141a and a second sub dielectric layer 141b. The first sub dielectric layer 141a and the second sub dielectric layer 141b have different dielectric constants. For example, the dielectric constant of the first sub dielectric layer 141a may be ε1, and the dielectric constant of the second sub dielectric layer 141b may be ε2 greater than ε1. Further, in some embodiments, the refractive indices of the first sub dielectric layer 141a and the second sub dielectric layer 141b may be the same. Even though the dielectric constants of the first sub dielectric layer 141a and the second sub dielectric layer 141b are different from each other, when the refractive indices are the same, the incident angle of light at the interface between the first sub dielectric layer 141a and the second sub dielectric layer 141b Regardless, the light path may not be refracted.

The distance between the bottom surface and the top surface of the first sub dielectric layer 141a, that is, the height d _{1 of the} cross section of the first sub dielectric layer 141a may be different according to the horizontal position. For example, if the lower surface of the first sub-dielectric layer 141a is flat but the upper surface of the first sub-dielectric layer 141a is formed as a curved surface, the height may be different according to the position in the horizontal direction. The exemplary first sub-dielectric layer 141a has a hemispherical or convex lens shape in cross section. Although not shown, the shape of the first sub dielectric layer may be a concave lens shape.

The second sub dielectric layer 141b is formed on the first sub dielectric layer 141a. The second sub dielectric layer 141b may be formed to completely cover the first sub dielectric layer 141a.

The arrangement of the first sub dielectric layer 141a may be a reference for dividing the liquid crystal lens 1110 into two or more unit lens sections L1 and L2. As shown in FIG. 14, when a plurality of unit patterns having a convex lens shape in which the first sub-dielectric layers 141a are interconnected are arranged, a unit lens section may be provided for each pattern. If each pattern of the first sub-dielectric layer 141a is substantially the same, it is obvious that the electro-optical characteristics of each unit lens section will be substantially the same. In the cross-sectional view of FIG. 14, the plurality of convex lens-shaped patterns are connected to the point N1, and the connection point N1 is located directly above the upper surface 130_1 of the liquid crystal layer 130. The same is true even if the liquid crystal layer 130 is spaced apart from the upper surface 130_1 and the lower end of each convex pattern is connected to the surface.

Meanwhile, in one unit lens section L1 and L2, capacitances between the upper and lower surfaces 141_1 and 141_2 of the dielectric layer 141 are different depending on the horizontal position. The height of the first sub dielectric layer 141a at each horizontal position is referred to as d ₁ , the height of the second sub dielectric layer 141b is referred to as d ₂ , and the upper and lower surfaces 141_1 and 141_2 of the entire dielectric layer 141 are flat. Assuming parallel, the following equation can be established.

[Formula 1]

D = d ₁ + d ₂

However, in Equation 1, D is a constant between the upper and lower surfaces 141_1 and 141_2 of the entire dielectric layer 141.

The elastance 1 / C between the upper and lower surfaces 141_1 and 141_2 of the dielectric layer 141 at each horizontal position can be obtained by the following equation.

[Formula 2]

1 / C = 1 / C ₁ + 1 / C ₂ = d ₁ / ε ₁ S + d ₂ / ε ₂ S

However, in Equation 2, wherein C ₁ represents the capacitance of the first sub-dielectric layer 141a, C ₂ represents the capacitance of the second sub-dielectric layer 141b, and S represents the cross-sectional area.

Using Equations 1 and 2, Equation 3 below can be derived.

[Equation 3]

1 / C = (d ₁ ε ₂ + d ₂ ε ₁ ) / ε ₁ ε ₂ S = {(ε ₂ -ε ₁ ) d ₁ + Dε ₁ } / ε ₁ ε ₂ S

In Equation 3, since ε1, ε2, D, and S may all be treated as constants, the capacitance C and the elastance 1 / C of the dielectric layer 141 may be the height d1 of the first sub-dielectric layer 141a. It can be seen that depends on. If ε2 is greater than ε1 (ε2 − ε1) is positive, the elastance 1 / C of the dielectric layer 141 becomes larger as the height d1 of the first sub-dielectric layer 141a becomes larger.

Therefore, in the liquid crystal lens 1110 illustrated in FIG. 14, the graph of the elastance 1 / C of the dielectric layer 141 may be drawn in a pattern similar to the pattern of the first sub-dielectric layer 141a as shown in FIG. 15. This is similar to the distribution graph of the elastance 1 / C for each position of the liquid crystal lens dielectric layer 140 of FIG. 2 described with reference to FIG. 3B. Thus, it will be readily understood that the liquid crystal lens 1110 of FIG. 14 will also exhibit substantially the same electrical and optical characteristics as the liquid crystal lens 1100 of FIG. 2.

In the present embodiment, an example in which ε2 is larger than ε1 is given, but ε2 may be smaller than ε1 in the same structure. In this case, the following equation can be derived from Equation 2.

[Formula 4]

1 / C = (d ₁ ε ₂ + d ₂ ε ₁ ) / ε ₁ ε ₂ S = {(ε ₁ -ε ₂ ) d ₂ + Dε ₂ } / ε ₁ ε ₂ S

In Equation 4, since ε1, ε2, D, and S may all be treated as constants, the capacitance C and the elastance 1 / C of the dielectric layer 141 may be the height d2 of the second sub-dielectric layer 141b. It can be seen that depends on. Since ε1 is greater than ε2, (ε1-ε2) is positive. Therefore, the elastance 1 / C, which is the inverse of the capacitance of the dielectric layer 141, becomes larger as the height d2 of the second sub-dielectric layer 141b becomes larger. However, since the sum of d1 and d2 in Equation 1 is constant, d ₁ becomes smaller as d ₂ increases. Therefore, the elastance 1 / C of the dielectric layer 141 becomes larger as the height d1 of the first sub dielectric layer 141a is smaller.

Therefore, if ε ₂ is greater than ε ₁ in this embodiment, the graph of the elastance 1 / C of the liquid crystal lens 1110 dielectric layer 141 is the ella of the liquid crystal lens dielectric layer 140 of FIG. 2 described with reference to FIG. 3B. It will be shown similar to flipping the distribution graph of the stance 1 / C up and down. In this case, it can be easily expected that the liquid crystal lens 1110 will exhibit substantially the same electrical and optical characteristics as the liquid crystal lens 1103 of FIG. 12.

16 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 16, the liquid crystal lens 1111 according to the present exemplary embodiment is configured such that an upper surface of the first sub dielectric layer 142a is partially curved, and a part of which is flat, and the second sub dielectric layer 142b is formed. 14 has a structure partially covering the first sub dielectric layer 142a but not covering the flat surface of the first sub dielectric layer 142a. The upper surface of the second sub-dielectric layer 142b is formed of a flat surface, but is disconnected in the flat upper surface area of the first sub-dielectric layer 142a. Accordingly, the components of the top surface 142_1 of the dielectric layer 142 include not only the flat top surface of the second sub dielectric layer 142b but also the flat top surface of the first sub dielectric layer 142a. The lower surface 142_2 of the dielectric layer 142 includes a lower surface of the second sub dielectric layer 142b.

In the first section CS in which the top surface of the first sub dielectric layer 142a constitutes a curved surface, the distribution of the elastance 1 / C of the dielectric layer 142 is substantially the same as the embodiment of FIG. 14. On the other hand, in the second section PS in which the top surface of the first sub dielectric layer 142a forms a flat surface, the second sub dielectric layer 142b does not exist and only the first sub dielectric layer 142a exists. In addition, since the height of the first sub-dielectric layer 142a in the second period PS is also constant, the capacitance C of the entire dielectric layer 142 in the second period PS is the same. Therefore, on the assumption that ε ₂ is greater than ε ₁ , the graph of the elastance 1 / C of the dielectric layer 142 of the present embodiment shows a convex curve upward in the first section CS, but in the second section PS. It will have a straight line parallel to the section axis.

In the case of such an distribution of the elastance 1 / C, since the electric field applied to the liquid crystal layer 130 is different for each horizontal position in at least the first section CS, the liquid crystal molecules for each horizontal position in the second mode driving ( Are arranged to have different azimuth angles. Therefore, since the green lens structure is formed in at least the first section CS, the optical characteristics similar to those of the convex lens can be exhibited.

Meanwhile, in the second section PS, the electric field applied to the liquid crystal layer 130 is the same for each horizontal position. Accordingly, the electric field of the liquid crystal layer 130 may maintain the same azimuth angle of the liquid crystal molecules 135 over the entire second period PS. However, the azimuth angle of the liquid crystal molecules 135 may be affected not only by the corresponding electric field, but also by the azimuth angle and the neighboring electric fields of the neighboring liquid crystal molecules 135.

For example, the liquid crystal molecules 135 are sequentially disposed at an initial alignment angle of 0 ° at sequentially neighboring first to third horizontal points, and the liquid crystal molecules 135 of the first horizontal point are each positioned at 20 ° by an electric field. To have an azimuth angle, it is assumed that the liquid crystal molecules 135 at the second horizontal point and the third horizontal point are designed to have an azimuth angle of 10 ° by the electric field. In this case, although the liquid crystal molecules 135 of the second horizontal point are supposed to rotate by 10 ° by the electric field, they may be physically affected by the rotation of the neighboring first horizontal point liquid crystal molecules 135 and As a result, the liquid crystal molecules 135 of the second horizontal point may rotate at an azimuth angle smaller than 20 ° but larger than 10 °. Therefore, according to the designed electric field, even if the azimuth angle rapidly changes in a stepwise manner along the horizontal direction, the magnitude of the azimuth angle is gently changed when the liquid crystal molecules 135 are affected by the rotation of other adjacent liquid crystal molecules 135. Can be. Such a phenomenon may also be caused by the influence of a neighboring electric field.

In the embodiment of FIG. 16, the azimuth angle of the actual liquid crystal molecules 135 is larger than that of the dielectric constant distribution at the boundary between the first and second sections CS and the second section PS due to the influence of the liquid crystal molecules 135 and the neighboring electric field. Can be changed slowly. If the azimuth angle of the liquid crystal molecules 135 changes in the horizontal direction, the above-described green structure may be better generated, which may help to deflect the traveling direction of the light in the dielectric layer 142.

17 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 17, the liquid crystal lens 1112 according to the present exemplary embodiment differs from the embodiment of FIG. 14 in that the structure of the dielectric layer 143 is upside down. That is, the first sub-dielectric layer 143a has a shape in which an upper surface is flattened and a lower surface of the first sub dielectric layer 143a is a convex lens having a curved structure. The second sub dielectric layer 143b covers the first sub dielectric layer 143a under the first sub dielectric layer 143a. Also in the dielectric layer 143 structure of FIG. 17, since a different dielectric constant is implemented along the horizontal direction, the liquid crystal lens 1112 forms a green structure having a different refractive index along the horizontal direction. Here, the first dielectric constant of a sub-dielectric layer (143a) is ε _1, second dielectric constant of a sub-dielectric layer (143b) is larger ε case _2, in this embodiment a liquid crystal lens 1112 dielectric horizontal direction 143 than ε ₁ It is a matter of course that a parabolic graph in which the distribution of the elastance (1 / C) of the convex downwards is opposite to FIG. 15.

18 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 18, the liquid crystal lens 1113 according to the present exemplary embodiment illustrates a case where the cross section of the first sub dielectric layer 144a has a trapezoidal shape. The trapezoidal shape may include a first side 144a_1 and a second side 144a_2 facing in parallel to each other and an oblique portion 144a_3 connecting therebetween. In the section AS2 including the oblique portion 144a_3, similar to FIG. 17, the capacitance C of the entire dielectric layer 144 including the first sub dielectric layer 144a and the second sub dielectric layer 144b is horizontally aligned. It is different. Although not curved, the azimuth angles of the liquid crystal molecules 135 according to the difference in capacitance C are arranged differently in this section AS2 to induce a change in refractive index of the liquid crystal lens. Thus, since the green lens structure is formed, it can act as an optical lens that bends the optical path. Meanwhile, in the section AS1 including the first side 144a_1, since the height d1 of the first sub dielectric layer 144a and the height d2 of the second sub dielectric layer 144b are constant, the same overall dielectric constant and capacitance are the same. (C) may be represented. Accordingly, the electric field of the liquid crystal layer 130 may maintain the same azimuth angle of the liquid crystal molecules 135 over the entire area AS1 including the first side 144a_1. However, as described with reference to FIG. 16, the azimuth angle of the liquid crystal molecules 135 may be affected not only by the electric field but also by the azimuth angle and the neighboring electric field of the neighboring liquid crystal molecules 135, and thus, the liquid crystal may also be used in this section AS1. The magnitude of the azimuth 135 may vary slowly, resulting in a green lens structure.

The embodiment of FIG. 18 also illustrates a case in which the first sub dielectric layer 144a includes a plurality of unit patterns spaced apart from each other. Each unit pattern of the first sub dielectric layer 144a is surrounded by a second sub dielectric layer 144b.

Since the unit patterns of the first sub-dielectric layer 144a are separated from each other, there is a section BS in which only the second sub-dielectric layer 144b exists without the first sub-dielectric layer 144a in the horizontal direction. Herein, the section BS having only the second sub-dielectric layer 144b has the same dielectric constant, and thus the capacitance C is also the same. Accordingly, the electric field of the liquid crystal layer 130 in the same period BS will maintain the liquid crystal molecules 135 at the same azimuth angle. However, as described with reference to FIG. 16, the azimuth angle of the liquid crystal molecules 135 may be affected not only by the electric field but also by the azimuth angle and the neighboring electric field of the neighboring liquid crystal molecules 135, and thus, the liquid crystal is also in this section BS. The magnitude of the molecules 135 azimuth may vary slowly.

The unit patterns of the first sub dielectric layer 144a are disposed on the left and right sides of the section BS including only the second sub dielectric layer 144b. If the unit patterns of the first sub-dielectric layers 144a positioned at the left and right sides have the same shape, the azimuth angle of the liquid crystal molecules 135 in the section BS including only the second sub-dielectric layer 144b is the center of the same section BS. Will be distributed substantially symmetrically from CP). Accordingly, the liquid crystal lens 1113 may be divided into different unit lens sections L1 and L2 with respect to the center of the section BS having only the second sub-dielectric layer 144b.

As a result, the refractive index distribution in the second mode of the liquid crystal lens 1113 according to the present exemplary embodiment may be substantially similar to the liquid crystal lens 1112 of FIG. Therefore, it can operate as a predetermined green lens.

19 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 19, the liquid crystal lens 1114 according to the present exemplary embodiment is different from the exemplary embodiment of FIG. 18 in that the cross-sectional shape of the first sub dielectric layer 145a is rectangular. The rectangle includes the first side 145a_1 and the second side 145a_2 opposite to each other in parallel to the trapezoid, but the line connecting them is not the diagonal line but the first side 145a_1 and the second side ( The point being the line 145a_3 perpendicular to 145a_2 is different. Therefore, the liquid crystal layer 130 has the same height d1 of the first sub-dielectric layer 145a and height of the second sub-dielectric layer d2 in the section AS in which the first sub-dielectric layer 145a is formed. The same overall dielectric constant and capacitance (C) are shown. The section BS without the first sub-dielectric layer 145a is different from the above section AS but exhibits the same overall dielectric constant and capacitance C over the section BS. That is, the total dielectric constant and capacitance C change abruptly at the boundary between the lines 145a_3 perpendicular to the first side 145a_1 and the second side 145a_2 of the first sub-dielectric layer 145a, and at other points. There is no change in overall permittivity and capacitance (C). However, even in this case, as described with reference to FIG. 16, the azimuth angle of the liquid crystal molecules 135 may be affected not only by the electric field but also by the azimuth angle and the neighboring electric field of the neighboring liquid crystal molecules 135. Accordingly, the magnitude of the azimuth of the liquid crystal molecules 135 may be gently changed around the line 145a_3 perpendicular to the first side 145a_1 and the second side 145a_2 of the first sub-dielectric layer 145a. Green lens structures can be formed.

20 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 20, in the liquid crystal lens 1115 according to the present exemplary embodiment, the shape of the first sub dielectric layer 146a is the same as that of the embodiment of FIG. 19, but the first sub dielectric layer 146a is the second sub dielectric layer 146b. ) Is different from the embodiment of FIG.

In the present embodiment, despite the difference in arrangement of the first sub dielectric layer 146a, the height d1 of the first sub dielectric layer 146a in the section AS including the first sub dielectric layer 146a is shown in FIG. 19. Is equal to the height d1 of the first sub-dielectric layer 145a. In addition, the sum of the heights of the second sub dielectrics 146b in the same section AS is the same as the height of the second sub dielectrics 145b of FIG. 19. Thus, it can be readily seen that the overall dielectric constant and capacitance C of dielectric layer 146 are substantially the same as in FIG. 19 and will therefore operate in the same manner.

21 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 21, the dielectric layer 147 of the liquid crystal lens 1116 according to the present exemplary embodiment includes a dielectric layer medium 147b and a dopant 147a included therein. Dopant 147a has a different density distribution depending on the horizontal position in dielectric layer medium 147b.

The dielectric constant of the dielectric layer 147 is influenced not only by the dielectric constant of the dielectric layer medium 147b itself, but also by the content of the dopant 147a contained therein and its dielectric constant. For example, when the conductive material is used as the dopant 147a, the higher the content of the dopant 147a, the smaller the dielectric constant of the dielectric layer 147 relative to the dielectric constant of the dielectric layer medium 147b. When the dielectric constant of the dopant 147a is higher than that of the dielectric layer medium 147b, the dielectric constant of the dielectric layer 147 may be larger than that of the dielectric layer medium 147b.

The change in permittivity caused by the dopant 147a becomes larger as the content of the dopant 147a increases. Therefore, when the content of the dopant 147a is different depending on the horizontal position, it is possible to implement a different dielectric constant for each horizontal position of the dielectric layer 147. By controlling the permittivity, content, and distribution of the dopant 147a, it is possible to form the dielectric layer 147 having substantially the same horizontal permittivity distribution as the various embodiments previously exemplified.

FIG. 22 is a cross-sectional view illustrating an exemplary method of manufacturing the dielectric layer of FIG. 21. Referring to FIG. 22, after forming the second electrode 120 on the second substrate 102, forming the dielectric layer medium 147b thereon, the dopant 147a is ion implanted through the mask 310. . The dopant 147a injected into the dielectric layer medium 147b through the open portion 312 of the mask 310 diffuses through heat treatment or the like. At this time, by adjusting the heat treatment time or the like, it is possible to control the degree of diffusion to the periphery, thereby controlling the density distribution of the dopant 147a in the dielectric layer 147 in the horizontal direction.

FIG. 23 is a cross-sectional view illustrating another exemplary method of manufacturing the dielectric layer of FIG. 21. Referring to FIG. 23, a second electrode 120 is formed on a second substrate 102, a dielectric layer medium 147b is formed thereon, and a mask pattern 320 is formed on the dielectric layer medium 147b. do. The mask pattern 320 may be formed in a shape that exposes the open portion or has a different height in at least the horizontal direction. The mask pattern may for example be formed of photoresist.

Next, the dopant 147a is ion implanted. In this case, when the content and / or the implantation energy of the dopant 147a is adjusted, the implantation depth of the dopant 147a may be controlled. If the depth of implantation of the dopant 147a is designed to be smaller than the maximum height of the mask pattern 320, different dopant 147a density distributions may be controlled for each horizontal direction.

24 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 24, the liquid crystal lens 1117 according to the present exemplary embodiment is different from the exemplary embodiment of FIG. 14 in that the first sub dielectric layer 148a covers the third sub dielectric layer 148c. Accordingly, the dielectric layer 148 also includes a section including the first sub dielectric layer 148a and the second sub dielectric layer 148b for each horizontal position, but includes the first sub dielectric layer 148a, the second sub dielectric layer 148b, and the first sub dielectric layer 148b. It also includes a section including all three sub-dielectric layers 148c, where the dielectric constant of the dielectric layer 148 includes all of the dielectric constants and the corresponding heights of the three sub-dielectric layers 148a, 148b, and 148c.

As such, when the number of sub-dielectric layers 148a, 148b, and 148c is increased, various dielectric constant combinations may be implemented, which may be advantageous for fine tuning of the dielectric constant distribution of the dielectric layer 148.

25 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 25, the liquid crystal lens 1118 according to the present exemplary embodiment may have substantially the same shape and relative arrangement as the first sub dielectric layer 149a and the second sub dielectric layer 149b, but may be substantially similar to the embodiment of FIG. 14. The upper and lower surfaces of the first sub dielectric layer 149a and the second sub dielectric layer 149b include a third sub dielectric layer 149c which is flat and parallel to the embodiment of FIG. 14. The overall dielectric constant and capacitance (C) of the dielectric layer 149 for each horizontal position are influenced by the dielectric constant and height of the third sub dielectric layer 149c as well as the first sub dielectric layer 149a and the second sub dielectric layer 149b. . However, since the third sub dielectric layer 149c has the same height for each horizontal position, the distribution of the dielectric constant for each horizontal position will be similar to that of FIG. 15. In the present exemplary embodiment, the third sub dielectric layer 149c is formed under the first sub dielectric layer 149a and the second sub dielectric layer 149b. However, the third sub dielectric layer 149c is the first sub dielectric layer 149c. 149a) and second sub-dielectric layer 149b, or both below and over.

26 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 26, in the liquid crystal lens 1119 according to the present embodiment, the dielectric layer 150 may include not only the first sub dielectric layer 150a and the second sub dielectric layer 150b, but also the third sub dielectric layer 150c and the second sub dielectric layer 150c thereon. The fourth sub-dielectric layer 150d is different from the embodiment of FIG. 14. The shape and arrangement of the first sub dielectric layer 150a and the second sub dielectric layer 150b are substantially the same as in FIG. 14. The shape and arrangement of the third sub dielectric layer 150c and the fourth sub dielectric layer 150d are substantially the same as the shape and arrangement of the first sub dielectric layer 150a and the second sub dielectric layer 150b. That is, the embodiment of FIG. 26 illustrates a case in which the dielectric layer 141 of FIG. 14 is stacked in two layers. Accordingly, the green lens may have a refractive index distribution that is substantially the same as that of the liquid crystal lens 1110 of FIG. The dielectric constants of the third sub dielectric layer 150c and the fourth sub dielectric layer 150d may be the same as or different from those of the first sub dielectric layer 150a and the second sub dielectric layer 150b, respectively.

27 and 28 are cross-sectional views of liquid crystal lenses according to other exemplary embodiments of the present invention. The liquid crystal lens 1120 of FIG. 27 illustrates a case where the size and pitch of the unit pattern of the third sub dielectric layer 151c is smaller than that of the first sub dielectric layer 151a. In detail, the size and pitch of the unit pattern of the third sub dielectric layer 151c are half of the first sub dielectric layer 151a. This structure is advantageous for finer control over the overall permittivity of the dielectric layer 151. Reference numerals 151b and 151d refer to the second sub dielectric layer and the fourth sub dielectric layer, respectively.

The liquid crystal lens 1121 of FIG. 28 illustrates a case in which the unit pattern of the third sub dielectric layer 152c has the same size as that of the first sub dielectric layer 152a but has a staggered arrangement. Such a structure may enable more control of the permittivity distribution. Reference numerals 152b and 152d refer to the second sub dielectric layer and the fourth sub dielectric layer, respectively.

29 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 29, the liquid crystal lens 1122 according to the present exemplary embodiment differs from the embodiment of FIG. 26 in that a third sub dielectric layer 153c and a fourth sub dielectric layer 153d are formed under the liquid crystal layer 130. Is the point. The first electrode 110 is disposed under the third sub dielectric layer 153c and the fourth sub dielectric layer 153d. The first sub dielectric layer 153a and the second sub dielectric layer 153b are substantially the same as in FIG. 26. Therefore, since the electro-optical structure of the present embodiment is substantially the same as that of FIG. 26, a green lens substantially similar thereto can be realized.

26 to 29 illustrate a case in which the unit patterns of the first sub dielectric layer and the third sub dielectric layer have convex surfaces upward, at least one of the unit patterns of the first sub dielectric layer and the third sub dielectric layer; Furthermore, of course, everyone may have a curved surface that is convex downward as in the embodiment of FIG. 17.

30 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 30, in the liquid crystal lens 1123 according to the present exemplary embodiment, the second electrode 121 is not disposed on the dielectric layer 154 and the liquid crystal layer 130, and specifically, in the dielectric layer 154. The point disposed between the first sub dielectric layer 154a and the second sub dielectric layer 154b is different from the embodiment of FIG. 17. Since the upper surface of the first sub-dielectric layer 154a forms a curved surface, the second electrode 121 conformally formed on the upper surface of the first sub-dielectric layer 154a may also be formed to form a curved surface. Only the first sub dielectric layer 154a is interposed between the second electrode 121 and the upper surface 130_1 of the liquid crystal layer 130 without the second sub dielectric layer 154b.

Although the dielectric constant of the first sub dielectric layer 154a is the same along the horizontal direction, the height d1 of the first sub dielectric layer 154a is different along the horizontal direction. Therefore, it has a different elasticity (1 / C) distribution for each horizontal direction. That is, in the section in which the height d1 of the first sub-dielectric layer 154a is the lowest, the elastance 1 / C value is the smallest, but as the height increases, the elastance 1 / C value also becomes large. Therefore, it can be seen that the voltage applied to the upper surface 130_1 of the liquid crystal layer 130 along the horizontal direction will also be different. As a result, the azimuth angles of the liquid crystal molecules 135 are different for each horizontal direction when the second mode is driven, thereby implementing the green lens structure.

In this embodiment, the dielectric constant of the second sub dielectric layer 154b does not affect the electric field applied to the liquid crystal layer 130. Therefore, the second sub dielectric layer 154b may be omitted.

31 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 31, the liquid crystal lens 1124 according to the present exemplary embodiment may cover the third sub dielectric layer 155c and the third sub dielectric layer 155c having an upper surface curved under the liquid crystal layer 130. 30D is disposed and the first electrode 111 is formed between the third sub dielectric layer 155c and the fourth sub dielectric layer 155d, which is different from the embodiment of FIG. 30. The third sub dielectric layer 155c, the fourth sub dielectric layer 155d, and the first electrode 111 may include a first sub dielectric layer 155a, a second sub dielectric layer 155b, and a first sub dielectric layer 155b under the liquid crystal layer 130. The two electrodes 121 may be disposed in substantially the same shape and arrangement.

In the present exemplary embodiment, the voltage applied to the lower surface 130_2 as well as the upper surface 130_1 of the liquid crystal layer 130 may be different along the horizontal direction. Therefore, the difference between the electric fields formed on the upper and lower surfaces 130_1 and 130_2 of the liquid crystal layer 130 may be doubled, thereby facilitating the implementation of the green lens structure.

32 is a cross-sectional view of a liquid crystal lens according to still another embodiment of the present invention. Referring to FIG. 32, the liquid crystal lens 1125 according to the present exemplary embodiment further includes an optical lens 160 on the second electrode 120, specifically, on the second substrate 102. There is a difference from the embodiment of the. That is, the liquid crystal lens 1125 according to the present exemplary embodiment illustrates a structure in which the optical lens 160 having a convex lens shape is stacked on the liquid crystal lens 1110 of FIG. 14. The unit lens of the optical lens 160 may be arranged at substantially the same pitch as the single patterns of the first sub dielectric layer 141a. The optical modulation characteristics of the optical lens 160 may be combined with a green lens structure implemented by the liquid crystal layer 130 to modulate the optical path. For example, if the green lens exhibits condensing properties, the convex lens can make the focal length shorter. If the green lens exhibits divergence characteristics, the condensing characteristics of the convex lens cancel this, so that the divergence of the light and the degree of condensation can be alleviated. In addition, if divergence and condensation are controlled to be accurately canceled, the path may be changed so that light emitted through the green lens goes straight. If the optical lens 160 to be applied is a concave lens it is obvious that the opposite effect will be.

For more various light control, the size or pitch of the unit lens of the optical lens 160 may be designed to be different from that of the unit pattern of the first sub-dielectric layer 141a. In some other embodiments of the present invention, the optical lens 160 may be disposed under the first electrode 110, for example under the first substrate 101.

33 is a perspective view of a liquid crystal lens according to still another embodiment of the present invention. In the liquid crystal lens 1127 according to the exemplary embodiment of FIG. 33, the dielectric layer 156 maintains substantially the same pattern along the third direction Z perpendicular to the first direction X and the second direction Y. FIG. Illustrate the case. That is, in the present exemplary embodiment, the first sub dielectric layer 156a is formed in a lenticular type extending along the third direction Z. Therefore, as in the case of the lenticular lens, the light modulation characteristics of the liquid crystal lens along the third direction Z may also be maintained uniformly. Reference numeral 156b is a second sub dielectric layer.

34 is a perspective view of a liquid crystal lens according to still another embodiment of the present invention. The liquid crystal lens 1128 according to the exemplary embodiment of FIG. 34 illustrates a case where the pattern of the dielectric layer 157 is changed along a third direction Z perpendicular to the first and second directions X and Y. FIG. That is, in the present embodiment, a plurality of unit patterns are also arranged along the third direction Z. FIG. The first sub dielectric layer 157a is formed of a micro lens type. Thus, it will be appreciated that they will exhibit substantially similar light modulation characteristics as micro lenses. Reference numeral 157b is a second sub dielectric layer.

33 and 34 may be applied in combination with various embodiments described by way of example in cross-section.

As described above with reference to FIG. 1, the liquid crystal lenses described above may form a display device together with a light providing device. In addition, since the light path can be freely changed and controlled, it may be applied to various devices using light such as solar cells and image sensors.

Hereinafter, a specific example of implementing a display capable of 2D / 3D switching while using a liquid crystal lens with a display panel will be described in detail.

35 is a cross-sectional view of a display device according to an exemplary embodiment of the present invention. 36 is a cross-sectional view for describing an exemplary operation of the display device in the second mode. 35 and 36 show an example in which the liquid crystal lens according to the embodiment of FIG. 14 is employed as the liquid crystal lens and the liquid crystal display panel is applied as the light providing device.

35 and 36, the display device 300 according to an exemplary embodiment of the present invention includes a liquid crystal display panel 200 and a liquid crystal lens 1110.

The liquid crystal display panel 200 includes a lower substrate 210 and an upper substrate 220 facing each other, and a liquid crystal molecule layer 230 interposed therebetween.

Pixel electrodes 211 are formed in the plurality of pixel areas PA1-PA12 defined to be arranged in a matrix form on the lower substrate 210. The pixel electrode 211 is connected to a switching element such as a thin film transistor to receive a pixel voltage individually.

The common electrode 224 facing the pixel electrode 211 is disposed under the upper substrate 220. R, G, and B color filters 221 may be disposed on the upper substrate 220 corresponding to each pixel area PA1 to PA12. The black matrix 222 may be formed at the boundary of the pixel areas PA1 to PA12. The planarization layer 223 may be interposed between the color filter 221 and the common electrode 224.

The liquid crystal molecule layer 230 is interposed between the lower substrate 210 and the upper substrate 220. The liquid crystal molecules 235 of the liquid crystal molecule layer 230 are rotated by an electric field formed between the pixel electrode 211 and the common electrode 224 to control the transmittance of the liquid crystal display panel 200.

Polarizers (not shown) may be attached to the outside of the lower substrate 210 and the upper substrate 220, respectively. In some embodiments, a polarizer (not shown) may also be attached to an outer surface of the first substrate 101 of the liquid crystal lens 1110. In this case, the polarizer on the upper substrate 220 may be omitted.

A backlight assembly (not shown) may be disposed below the liquid crystal display panel 200.

The liquid crystal lens 1110 is disposed on the liquid crystal display panel 200. In the drawing, an example in which the liquid crystal lens 1110 is spaced apart from the liquid crystal display panel 200 is illustrated, but is not limited thereto. The liquid crystal lens 1110 may be attached to the liquid crystal display panel 200.

Each unit lens section L1 and L2 of the liquid crystal lens 1110 may be disposed to correspond to the plurality of pixel areas PA1 to PA12 of the liquid crystal display panel 200. 35 illustrates an example in which six pixel areas and one unit lens section correspond to each other. That is, six pixel areas of R, G, B, R, G, and B are arranged in the width of one unit lens section.

In such a display device, when the liquid crystal lens 1110 is driven in the first mode, the liquid crystal lens 1110 does not particularly modulate the optical path, and thus the display device 300 may display a two-dimensional image. On the other hand, when the liquid crystal lens 1110 is driven in the second mode, the display device 300 may display a 3D image. Reference is made to FIG. 36 for a more detailed description.

36 is a cross-sectional view for describing an exemplary operation of the display device in the second mode. Referring to FIG. 36, the optical characteristic of the liquid crystal lens 1110 in the second mode is similar to that of the convex lens, as described with reference to FIGS. 14 and 15. Therefore, the light incident on the unit lens section from the three pixel regions R, G, and B arranged on the left side with respect to the central portion of each unit lens section L1, L2 passes through the left region of the convex lens. Since is modulated, it is bent in the right direction. On the other hand, the light incident on the unit lens section from three pixel regions R, G, and B arranged on the right side with respect to the center of each unit lens section is modulated as if the light path passes through the right region of the convex lens. Bend in the direction. When the above lights are input to the left eye E1 and the right eye E2 of the observer, respectively, the observer may recognize the 3D image.

35 and 36 illustrate that six pixel areas are arranged within the width of one unit lens section, but more pixel areas may be arranged within the width of one unit lens section. Three-dimensional image driving becomes possible. In addition, if the voltages applied to the first electrode and the second electrode of the liquid crystal lens are adjusted as described above, the focal length of the liquid crystal lens can be changed, so that the distance at which the three-dimensional viewing is possible can be adjusted. For example, it is convenient for the observer to operate the viewpoint switching mode on the display device through the remote controller, and in response to the voltage applied to the first electrode and the second electrode of the liquid crystal lens to be sequentially changed to move the viewpoint forward and backward. The viewpoint of viewing the 3D image can be found.

In some other embodiments of the present invention, the common voltage applied to the common electrode of the liquid crystal display panel may be the same as the first voltage applied to the first electrode of the liquid crystal lens or the second voltage applied to the second electrode. In this case, the driving circuit can be simplified.

Also, in some other embodiments of the present invention, the upper substrate of the liquid crystal display panel may be shared with the first substrate of the liquid crystal lens. Therefore, any one of the upper substrate of the liquid crystal display panel and the first substrate of the liquid crystal lens may be omitted. Furthermore, one of the common electrode of the liquid crystal display panel and the first electrode of the liquid crystal lens may be omitted and shared.

35 and 36 illustrate that the liquid crystal display panel 200 is applied as a light providing device. However, as described above, OLEDs, LEDs, inorganic ELs, FEDs, SEDs, PDPs, CRTs, electrophoretic displays, and the like are described. You can also apply. Embodiments for this will be easily deduced by those skilled in the art from the embodiments of FIGS. 35 and 36, and thus detailed descriptions thereof will be omitted in order to avoid obscuring the present invention.

35 and 36 illustrate a case in which the liquid crystal lens 1110 according to the embodiment of FIG. 14 is used as the liquid crystal lens, other liquid crystal lenses according to various embodiments of the present invention may be applied. Is self explanatory.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. I can understand that. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

110: first electrode 120: second electrode
130: liquid crystal layer 135: liquid crystal molecules
140: dielectric layer 1100: liquid crystal lens

Claims (41)

First and second electrodes facing each other;
A liquid crystal layer interposed between the first electrode and the second electrode, the upper and lower surfaces of which are flat; And
A dielectric layer interposed between the second electrode and the liquid crystal layer;
The dielectric layer may include a section in which capacitance between an upper surface and a lower surface of the dielectric layer varies along a horizontal direction. The method according to claim 1,
And wherein the capacitance distribution between the top and bottom surfaces of the dielectric layer in the horizontal direction comprises a parabola that is convex upward or convex downward. The method according to claim 1,
The dielectric layer has a flat upper and lower liquid crystal lens. The method according to claim 1,
The liquid crystal lens includes a first unit lens section representing a first light modulation characteristic and a second unit lens section representing a second light modulation characteristic. 5. The method of claim 4,
And the first and second light modulation characteristics are the same. The method according to claim 1,
The liquid crystal lens includes a plurality of unit lens sections, and the dielectric layer includes a section in which capacitance between the upper surface and the lower surface changes in a horizontal direction for each unit lens section. The method of claim 6,
And a capacitance distribution between upper and lower surfaces of the dielectric layer having the same position in the horizontal direction for each unit lens section. The method of claim 6,
When different voltages are applied to the first electrode and the second electrode, the liquid crystal layers of the unit lens sections each form a green lens structure. The method according to claim 1,
The first and second electrodes are liquid crystal lenses, respectively. The method according to claim 1,
And the first electrode and the second electrode are arranged in parallel with each other. The method according to claim 1,
Wherein said dielectric layer comprises a dielectric layer medium and dopants distributed at different densities depending on horizontal positions within said dielectric layer medium. First and second electrodes facing each other;
A liquid crystal layer interposed between the first electrode and the second electrode, the upper and lower surfaces of which are flat; And
A dielectric layer interposed between the second electrode and the liquid crystal layer, the dielectric layer including a first sub dielectric layer having a first dielectric constant and a second sub dielectric layer having a second dielectric constant different from the first dielectric constant,
The dielectric layer may include a section in which a height of at least one of the first sub dielectric layer and the second sub dielectric layer is changed along the horizontal direction. The method of claim 12,
And a sum of the height of the first sub dielectric layer and the height of the second sub dielectric layer in a horizontal direction. The method of claim 12,
The refractive index of the first sub dielectric layer and the refractive index of the second sub dielectric layer are the same. The method of claim 12,
The first sub-dielectric layer includes a plurality of unit patterns interconnected. The method of claim 15,
At least one of the plurality of unit patterns has a cross-section that includes a curved portion. The method of claim 12,
The first sub-dielectric layer includes a plurality of unit patterns spaced apart from each other. The method of claim 17,
Each unit pattern of the first sub dielectric layer is surrounded by the second sub dielectric layer. 19. The method of claim 18,
At least one of the plurality of unit patterns of the first sub-dielectric layer has a hemispherical, trapezoidal, convex, or concave lens shape in cross section. The method of claim 12,
The dielectric layer has a flat upper and lower liquid crystal lens. The method of claim 12,
The first and second electrodes are liquid crystal lenses, respectively. The method of claim 21,
And the first electrode and the second electrode are arranged in parallel with each other. The method of claim 12,
And a further optical lens disposed below the first electrode or above the second electrode. A first electrode;
A liquid crystal layer formed on the first electrode and having a flat upper and lower surfaces;
A dielectric layer formed on the liquid crystal layer, the upper surface of which includes a curved surface; And
And a second electrode conformally formed on an upper surface of the dielectric layer. 25. The method of claim 24,
The dielectric layer includes a plurality of unit patterns interconnected. 25. The method of claim 24,
The first and second electrodes are liquid crystal lenses, respectively. Light providing device; And
A liquid crystal lens disposed on the light providing device,
A first electrode and a second electrode facing each other,
A liquid crystal layer interposed between the first electrode and the second electrode, the upper and lower surfaces of which are flat; and
A dielectric layer interposed between the second electrode and the liquid crystal layer;
The dielectric layer includes a liquid crystal lens including a section in which capacitance between an upper surface and a lower surface of the dielectric layer varies along a horizontal direction. 28. The method of claim 27,
The light providing device includes a display panel. 29. The method of claim 28,
The display panel includes an organic light emitting diode (OLED), an LED, an electroluminescent display (EL), a field emission display (FED), a surface-conduction electron-emitter display (SED), a plasma display panel (PDP), and a cathode (CRT) A display device, which is any one of a ray tube, a liquid crystal display (LCD), and an electrophoretic display (EPD). 29. The method of claim 28,
The display panel includes a plurality of pixel areas arranged in a matrix form.
The liquid crystal lens includes a plurality of unit lens sections, and the dielectric layer includes a section in which capacitance between the upper surface and the lower surface varies in a horizontal direction for each unit lens section.
And at least two pixel areas within a width of each unit lens section. 31. The method of claim 30,
And a capacitance distribution between upper and lower surfaces of the dielectric layer having the same position in the horizontal direction for each of the unit lens sections. 28. The method of claim 27,
And a distribution of capacitances between an upper surface and a lower surface of the dielectric layer in the horizontal direction includes a parabola that is convex upward or convex downward. 28. The method of claim 27,
The liquid crystal lens includes a plurality of unit lens sections, and the dielectric layer includes a section in which capacitance between the upper surface and the lower surface varies in a horizontal direction for each of the unit lens sections. Light providing device; And
A liquid crystal lens disposed on the light providing device,
A first electrode and a second electrode facing each other,
A liquid crystal layer interposed between the first electrode and the second electrode, the upper and lower surfaces of which are flat; and
A dielectric layer interposed between the second electrode and the liquid crystal layer, the dielectric layer including a first sub dielectric layer having a first dielectric constant and a second sub dielectric layer having a second dielectric constant different from the first dielectric constant,
The dielectric layer includes a liquid crystal lens including a section in which a height of at least one of the first sub dielectric layer and the second sub dielectric layer is changed along the horizontal direction. The method of claim 34, wherein
The light providing device includes a display panel. 36. The method of claim 35 wherein
The display panel includes an organic light emitting diode (OLED), an LED, an electroluminescent display (EL), a field emission display (FED), a surface-conduction electron-emitter display (SED), a plasma display panel (PDP), and a cathode (CRT) A display device, which is any one of a ray tube, a liquid crystal display (LCD), and an electrophoretic display (EPD). 36. The method of claim 35 wherein
The display panel includes a plurality of pixel areas arranged in a matrix form.
The first sub-dielectric layer includes a plurality of unit patterns interconnected.
And two or more pixel areas disposed within a width of each unit pattern. 36. The method of claim 35 wherein
The display panel includes a plurality of pixel areas arranged in a matrix form.
The first sub dielectric layer includes a plurality of unit patterns spaced apart from each other,
And at least two pixel areas for each pitch of each unit pattern. The method of claim 34, wherein
And a sum of the height of the first sub dielectric layer and the height of the second sub dielectric layer is constant along a horizontal direction. The method of claim 34, wherein
The refractive index of the first sub dielectric layer and the refractive index of the second sub dielectric layer are the same. Light providing device; And
A liquid crystal lens disposed on the light providing device,
First electrode,
A liquid crystal layer formed on the first electrode and having a flat upper and lower surfaces;
A dielectric layer formed on the liquid crystal layer, the top surface of which includes a curved surface, and
And a liquid crystal lens including a second electrode conformally formed on an upper surface of the dielectric layer.

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